package wx.xml.stax.api.stream;

import java.util.Iterator;

import wx.xml.stax.api.stream.events.XMLEvent;

/**
 * This is the top level interface for parsing XML Events.  It provides
 * the ability to peek at the next event and returns configuration
 * information through the property interface.
 *
 * @author Copyright (c) 2003 by BEA Systems. All Rights Reserved.
 * @version 1.0
 * @see XMLInputFactory
 * @see XMLEventWriter
 */
public interface XMLEventReader extends Iterator {
    /**
     * Get the next XMLEvent
     *
     * @throws XMLStreamException     if there is an error with the underlying XML.
     * @throws NoSuchElementException iteration has no more elements.
     * @see XMLEvent
     */
    public XMLEvent nextEvent() throws XMLStreamException;

    /**
     * Check if there are more events.
     * Returns true if there are more events and false otherwise.
     *
     * @return true if the event reader has more events, false otherwise
     */
    public boolean hasNext();

    /**
     * Check the next XMLEvent without reading it from the stream.
     * Returns null if the stream is at EOF or has no more XMLEvents.
     * A call to peek() will be equal to the next return of next().
     *
     * @throws XMLStreamException
     * @see XMLEvent
     */
    public XMLEvent peek() throws XMLStreamException;

    /**
     * Reads the content of a text-only element. Precondition:
     * the current event is START_ELEMENT. Postcondition:
     * The current event is the corresponding END_ELEMENT.
     *
     * @throws XMLStreamException if the current event is not a START_ELEMENT
     *                            or if a non text element is encountered
     */
    public String getElementText() throws XMLStreamException;

    /**
     * Skips any insignificant space events until a START_ELEMENT or
     * END_ELEMENT is reached. If anything other than space characters are
     * encountered, an exception is thrown. This method should
     * be used when processing element-only content because
     * the parser is not able to recognize ignorable whitespace if
     * the DTD is missing or not interpreted.
     *
     * @throws XMLStreamException if anything other than space characters are encountered
     */
    public XMLEvent nextTag() throws XMLStreamException;

    /**
     * Get the value of a feature/property from the underlying implementation
     *
     * @param name The name of the property
     * @return The value of the property
     * @throws IllegalArgumentException if the property is not supported
     */
    public Object getProperty(java.lang.String name) throws java.lang.IllegalArgumentException;

    /**
     * Frees any resources associated with this Reader.  This method does not close the
     * underlying input source.
     *
     * @throws XMLStreamException if there are errors freeing associated resources
     */
    public void close() throws XMLStreamException;

    public Location getLocation();
}



